Special Health Care Needs Flashcards
What is the definition of special health care needs?
Any physical, developmental, mental, sensory, behavioral, cognitive or emotional impairment or limiting condition that requires medical management, healthcare intervention and/or use of specialized services or programs
How many children with SHCN under 19 years of age in the US?
10.2 million (representing 14% of all US children) and <6000 pediatric dentists Different source: 12.5 million and 18% of children in the US
How many adolescents in the US with SHCN cross into adulthood?
750,000
When should specific transition planning begin for those patients with SHCN?
Between the ages of 14-16 years
What is the most common category of unmet health care for children with special needs?
Dentistry!
T/F:According to the Americans with Disabilities Act (AwDA), the dental office is a place of public accommodation.
True. Thus, dentists are obligated to be familiar with these regulations and ensure compliance. Failure to accommodate pts with SHCN could be considered discrimination and violation of federal and/or state law! E.g. provide wheelchair ramps, disabled-parking spaces
T/F: Children with SHCN are more likely to be victims of physical abuse, sexual abuse, and neglect compared to those w/o disabilities.
True
What are the SBE prophylaxis guidelines?
- Prosthetic cardiac valve of prosthetic material used for cardiac valve repair
- Previous infective endocarditis
- CHD (congenital heart disease) - Unrepaired cyanotic CHD, including palliative shunts/conduits - Completely repaired cong heart defect with prosthetic material or device, whether placed by surgery or catheter, during first 6 months after procedure (bc endothelialization of prosthetic materials occurs within 6 months after the procedure) - Repaired CHD with residual defects at or adjacent to site of prosthetic patch or prosthetic device (which inhibit endothelialization)
- Cardiac transplant recipients who develop cardiac valvulopathy **these cardiac conditions are associated with the highest risk of adverse outcome from infective endocarditis
Does an anesthetic injection through non-infected tissue need SBE prophylaxis?
No. Also, SBE prophylaxis not required for X-raysremovable prosth or ortho appliance placement ortho appliance adjustmentsortho bracket placementexfoliation of deciduous teethbleeding from trauma to lips or oral mucosa
What are some non-cardiac factors that can place pt with compromised immunity at risk for distant-site infection from dental procedure?
- Immunosuppression HIV, SCIDS (severe combined immunod), neutropenia, cancer chemo, hematopoietic stem cell or solid organ transplantation - head and neck radiotherapy - autoimmune disease (Juvenile arthritis, systemic lupus erythematosus) - sickle cell anemia - asplenism or s/p splenectomy - chronic steroid usage - diabetes - bisphosphonate therapy
What are AHA recommendation for abx px for indwelling catheters or medical devices?
AHA recommends abx px for - nonvalvular devices indicated only at time of placement to prevent surgical site infection* - indwelling vascular catheters (central lines) - cardiovascular implantable electronic devices (CIED) - VA, VC, VV shunts do require abx px (VAC) - VP shunt does not (does not involve any vascular structures) *AHA found no convincing evidence that microorganisms associated with dental procedures cause infection of nonvalvular devices at any time after implantation – most often gram negative staph or other microorganisms non-oral in origin associated with surgical implantation or other active infections
What patients are at increased risk of hematogenous total joint infection?
- All patients with a prosthetic total joint replacement - Previous prosthetic joint infection- Inflammatory arthropathies (e.g. RA, SLE) - Megaprosthesis - Hemophilia - Malnourishment - Compromised immunity
ADA/AAOS 2012 recommendations that are endorsed by the AAPD:
- Abx px not indicated for: - pins, plates, screws, or other hardware that is not within a synovial joint - nor routinely for most dental patients with total joint replacements Based on the fact that antibiotic prophylaxis has NOT shown a significant reduction in the risk of developing joint infections subsequent to dental procedures
What are considered high-risk dental procedures?
- All procedures that involve manipulation of gingival tissue or periapical region of teeth or perforation of the oral mucosa
Oral abx dosage for abx px:
Amoxicillin: 2g adult, 50 mg/kg child Allergy to pens or ampicillin => Cephalexin: 2g adult, 50 mg/kg child Clindamycin: 600 mg adult, 20 mg/kg child Azithromycin or clarithromycin: 500 mg adult, 15 mg/kg child
ABX PX for pt unable to take oral medications:
All given IM or IV Ampicillin 2g adult, 50 mg/kg child Cefazolin or ceftriaxon 1g adult, 50 mg/kg child Allergic to penicillin or ampicillin: Cefazolin or ceftriaxon 1g adult, 50 mg/kg child Clindamycin 600 mg adult, 20 mg/kg child
Amoxicillin is the drug of choice for SBE prophylaxis because of increased A. Compliance B. GI absorption C. Sustained serum levels A&B B&C
B and C
What type of chx is indicated for pts tx w/chemo or radiation?
Alcohol-free CHX because otherwise high alcohol content may cause discomfort and dehydrate the tissues in pts with mucositis.
Is flossing and ultrasonic toothbrushing recommended for all patients undergoing cancer therapy?
No, only for those that are properly trained. Brushing of teeth and tongue 2x day with soft brush or electric toothbrush is recommended regardless of hematological status If poor OH and/or perio disease, may use CHX rinses daily until tissue health improves or mucositis develops.
What are the important ANC values?
> 2000 : no need for abx px 1000 – 2000 : rx abx px (consider more abx if infection/unclear) < 1000 : defer elective dental care. In emergency, discuss abx coverage with medical team before proceeding with treatment. Pt may need hospitalization for dental management. <500 defer all care
What are important platelet counts?
> 75,000 doing awesome, no additional support needed 40k – 75k : consider platelet transfusion pre- and 24 hrs post-operatively. Use localized control measures like: sutures, hemostatic agents, pressure packs, gelatin foams < 40k : defer care. In emergency, discuss w/PMD platelet transfusions, bleeding control, hospital admission. Also use localized control like: microfibrillar collagen, topical thrombin and additional meds recommended by hematologist/oncologist like aminocaproic acid, tranexamic acid
How do cycles of chemo (and other therapies) typically affect blood counts?
Blood counts start falling 5-7 days after beginning of cycle. Stay low for 14-21 days Rise to normal a few days before next cycle begins. Ideally all dental tx complete before therapy begins. Otherwise, place ITR and delay non-acute dental tx.
How are dental procedures prioritized for pts undergoing cancer therapy?
FIRST: 1. Infections 2. Extractions 3. Periodontal care (scaling, px) 4. sources of tissue irritation THEN: 5. carious teeth (look at risk for pulp infection & pain) 6. RCT permanent tth 7. replacement faulty restorations Be aware that s/s periodontal disease may be decreased in immunosuppressed pts.
What is the recommendation for pulp therapy for primary teeth prior to cancer tx?
NO STUDIES showing safety. Definitive tx (EXT) preferred by clinicians Pulpal/PA/furcal infections during immunosuppression periods can become life-threatening Existing pulp/sscs should be monitored for signs internal resorption/failure to do infection
Recommendation for permanent tooth endo tx prior to cancer tx?
Symptomatic, non-vital permanent tth: do RCT > 1 wk before chemo bc need time to assess success of RCT Asymptomatic, non-vital perm tth RCT may be delayed until hematological status of pt is stable. Otherwise, EXT EXT followed by abx for 1 wk if RCT can’t be completed in single visit **determine etiology of PARL associated with RCT-txed teeth to diagnose pulpal infection, inflammatory rxn, apical scar, cyst, malignancy. If PARL associated with RCT tooth & no s/s infection, could be apical scar (no need for retreat or ext)
Recommendations for ortho/space maintainers during chemotherapy:
If OH poor, tx protocol or HCT conditioning has moderate to high risk of developing mucositis, remove appliances. If can’t remove, use wax/mouth guard to decrease tissue trauma If poorly fitting, remove bc can abrade mucosa and increase risk of microbial invasion of deeper tissues Simple things like B&L, LLHA that are not irritating may be left in place for pts with good OH. Removable appliances may be worn as tolerated. Clean them with antimicrobial solutions
Perio considerations for chemo therapies
Operculum should be excised if potential risk for infection d/t pericoronitis & if hematologic status allows. Perio assessment needed prior to bisphosphonate therapy part of cancer tx EXT for tth with poor prognosis that can’t be treated definitively w/perio therapy
What should be done with loose primary teeth during cancer tx?
Allow them to exfoliate naturally
Nonrestorable tth Root tips Tth with > 6mm perio pockets Symptomatic impacted teeth Teeth w/acute infections should be extracted ideally how far before therapy starts?
Ideally 2 weeks At least 7-10 days allow adequate healing
Do pediatric dentists encourage foam or super soft brushes?
No, we discourage them because they do not allow for effective cleaning – only use if pt develops moderate to severe mucositis Toothpicks and water irrigation devices should not be used when pt is pancytopenic (avoid tissue trauma)
Are lanolin or petroleum based products more effective for lip care?
Lanolin
Oral complications related to cancer therapies: 54%
mucositis salivary effects- reduced flow, thicker, lower pH opportunistic infx (fungal, viral, bacterial) oral bleeding: thrombocytopenia, others soft tissue necrosis dental sensitivity/pain: salivary changes, neurotoxic drugs, odontogenic infx, referred pain taste dysfunction mucosal and muscular fibrosis trismus, TMJ dysfunction nutritional deficiencies GVHD in HSCT craniofacial, dental development problems
Management of mucositis includes medicated mouth rinses
No. Recommend good OH, analgesics, non-medicated rinses like 0.9% saline or sodium bicarb rinse 4-6xday, parenteral nutrition as needed
What is palifermin and what is it recommended for?
Palifermin is keratinocyte growth factor-1Recently recommended for prevention of oral mucositis as prophylaxis and tx to decrease mucositis Observed to decrease incidence and duration of severe oral mucositis in pts undergoing conditioning w/high dose chemo with or without radiotherapy, followed by HCT (hematopoietic cell transplant)
What else is recommended for mucositis?
Coating agents like Amphojel Kaopectate hydroxypropylmethylcellulose Film-forming agents like Zilactin Gelclair low-level laser therapy – limited but encouraging evidence NOT RECOMMENDED: sucralfate, antimicrobial lozenges, pentoxifylline, and granulocyte-macrophage-colony stimulating factor mouthwash chlorhexidine not recommended for prevention of mucositis
What do “Philadelphia mouthwash” and “Magic Mouthwash” have?
Topical anesthetics. No significant evidence of the effectiveness or tolerability of these. Only provide short term pain relief. Lidocaine use may obtund or diminish taste and the gag reflex and/or result in a burning sensation, in addition to the possible cardiovascular and CNS effects
T/F: Prophylactic nystatin is effective for the prevention and/or treatment of fungal infections in cancer pts.
False
What dental side effects can vincristine or vinblastine (plant alkaloid chemo) have?
May present w/ deep, constant pain affecting mand molars in absence of odontogenic pathology. Pain usually transient & subsides shortly after dose reduction/cessation of chemo
Are saliva stimulating drugs approved for use in children?
No. Recommended: sugar-free chewing gum or candy, sucking tablets, special dentifrices for oral dryness, saliva substitutes, frequent water sipping, alcohol-free oral rinses, oral moisturizers, humidifier, fluoride rinses and gels
When can you start ortho on a child who has undergone cancer therapy?
After completion of all therapy and after at least a 2 year disease-free survival, when the risk of relapse is decreased and pt is no longer on immunosuppressive drugs
What are the 5 phases of Hematopoietic cell transplant?
Phase I: Preconditioning Phase II: Conditioning neutropenic phase Phase III: Engraftment to hematopoietic recovery Phase IV: Immune reconstitution/recovery from systemic toxicity Phase V: Long-term survival
How does HCT differ from other cancer therapies?
- HCT pt receives all the chemo and/or total body irradiation in just a few days before the transplant2. There will be prolonged immunosuppression following transplant.
Until when must elective dentistry be postponed after HCT?
Until immunologic recovery At least 100 days after HCT Longer if GVHD or other complications present *tx should be completed before pt becomes immunocompromised
Phase II: Conditioning neutropenic phase starts when and lasts how long?
Starts when pt admitted to hospital to begin transplant conditioning until 30 days post HCT - mucositis (begins 7-10 days after initiation & last abt 2 wks after end of conditioning) - xerostomia - oral pain - hemorrhage - opportunistic infections - taste dysfunction - neurotoxicity (including dental pain, muscle tremors) - TMD (pain, HA, joint pain) - GVHD (with allogeneic transplant) – severe inflammation/ mucositis *Dental tx usually not allowed in this phase due to severe immunosuppression
Phase III: Engraftment to hematopoietic recovery has what concerns? Lasts 1 month to 100 days
Complication severity decrease 3-4 wks after transplant Oral fungal and herpes simplex infections notable Acute GVHD xerostomia, hemorrhage, neurotox, TMD, granulomas/papillomas sometimes are observed Acute sensitivity to thermal stimuli btwn 2-4 months s/p tx w/spontaneous resolution w/in few months. Use topical F- to reduce symptoms.
Phase IV: Immune reconstitution/recovery from systemic toxicity starts when and involves what?
After day 100 s/p HCT Oral complications related to chronic toxicity: - salivary dysfunction (+xerostomia) - craniofacial growth abnormalities - late viral infections - oral chronic GVHD - oral squamous cell carcinoma Mucosal bacterial infections less frequently seen, unless pt is neutropenic or with severe chronic GVHD Exam + xrays can be done. Defer invasive dental tx in profoundly immunocompromised pts.
Phase V: Long-term survival Craniofacial, skeletal, and dental development complications occur for children under what age?
< 6yo at time of cancer therapy (<4 y.o. especially per Flaitz) - tooth agenesis - microdontia - crown disturbances (size, shape, enamel hypoplasia, pulp chamber anomalies) - root disturbances (early apical closure, blunting, changes in shape or length) - ectopic eruption - reduced mandibular length - reduced alveolar process height - malocclusion, facial deformities, skeletal hypoplasia - trismus - may experience permanent salivary gland hypofunction/dysfunction or xerostomia - increased caries risk Relapse can develop during stage V
When are dental malformations most severe for children undergoing chemo/radiation therapy?
< age 6, Especially < 4yo - tooth agenesis - crown malformation/microdontia - enamel hypoplasia - root V shape, blunting, altered root number
What are the 2 types of Hematopoietic Stem Cell Transplantation? (HSCT)
- BMT 2. PBSCT Peripheral blood stem cell transplantation Purpose: to restore stem cells that are destroyed by doses of chemo or radiation therapy
What are the 3 types of transplants?
- Autologous: pt’s own stem cells 2. Syngeneic: stems from identical twin 3. Allogenic: stems from HLA-compatible donor, related or non-related
What are the two types of cancer most frequently treated with HSCT?
Leukemia + lymphoma Also, aplastic anemia, solid tumors like neuroblastoma, inborn and acquired immune disorders
What are the 4 phases of HSCT care?
- Pretransplantation phase 2. Conditioning/ neutropenic phase 3. Initial engraftment to hematopoietic reconstitution 4. Immune reconstitution/late post-transplantation
What period lasts from day 0 to 30 days post-HSCT?
Conditioning / neutropenic Acute GVHD begins at this time
When do complications from HSCT begin to decrease?
4 wks after transplantation GVHD may be present sensitivity to thermal stimuli
When does GVHD develop?
Allogenic transplant Transplanted T-lymphocytes recognize host’s cells as foreign Acute: occurs up to day 120 post-transplant - rash, GI, hepatitis - mucosal atrophy/erythema/lichenoid rxn tx: steroids/immunosuppressants Chronic GVHD: occurs btwn 70-500 days post-transplant (avg 6 months) - 20-50% of children (higher in adults) - immune dysfn or autoimmune - many organs affected: skin, liver, joints, eyes, mouth, lung, muscle - in addition to atrophy/erythema/lichenoid/xerostomia/ulcers/gingivitis/caries/perio/trismus/taste dysfunction - cyclosporine => gingival overgrowth
Herpangina is caused by what virus?
Coxsackie A (enterovirus) also causes hand food mouth dx 2-6 red macules, vesicles, ulcers on the soft palate, tonsillar pillars; ulcers heal in 7-10 days sore throat, dysphagia, fever, rhinorrhea, cough, vomiting, headache, diarrhea
DiGeorge syndrome is what chromosomal anomaly?
Deletion of 22q11.2
DiGeorge is also called what?
Velocardiofacial syndrome VCFS
What is a good way to remember DiGeorge?
CATCH – 22 C – cardiac A – abnormal facies T – thymic hypoplasia C – cleft H – hypocalcemia 22 – chromosome 22q11.2
C- cardiac anomalies seen in DiGeorge/VCFS
- VSD - truncus arteriosus (one vessel instead of two leaving heart)- Tetralogy of Fallot
What four malformations of the heart does Tetralogy of Fallot exhibit?
- Pulmonary stenosis (narrowing of R V outflow) 2. Overriding aorta (aorta situated above the VSD and connected to both R and L Ventricle) 3. VSD (hole btwn R & L V) 4. RV Hypertrophy (R ventricle extra muscular bc of obstruction to outflow)
A – Abnormal facies of DiGeorge
Small, low set ears wide set eyes hooded eyes long face flattened philtrum
T – thymic hypoplasia results in what? (DiGeorge)
T-cells mature in the thymus. Children with small or missing thymus have poor immune function and frequent, severe infections Thymus decreases in size & function with age.
C - clefting (DiGeorge)
Cleft palate is very common (overt or submucous cleft) May cause Speech problems VPI
DiGeorge hypocalcemia results from what?
Hypoparathyroidism Parathyroid glands regulate PTH if less PTH then you have low levels of Ca and high levels of Phosphorus in the blood
Dental findings in Hypothyroidism (cretinism)
Delayed tooth eruption but normal development; +/- enamel hypoplasia; enlarged tongue, lips (glycosaminoglycans) also FTT, short, generalized edema, puffy face, husky voice, intellectual disability mandible underdeveloped, maxilla overdeveloped
When does cleft palate/lip repair occur?
Lip – at 3 months Palate – at 10-12 months because negatively impacts speech development if done later
With what frequency does clefting occur?
1:500 – 1:1000 Prevalences (AAPD COMP REVIEW) 1/2000 cleft palate alone 1/1000 cleft lip alone CL+CP 45%, CP alone 30%, CL alone 25% genetic, environmental causes (maternal alcohol use, cig smoking, folic acid deficiency, meds)
At what point developmentally does clefting occur?
4-7th week of gestation
Does cleft lip have a gender predilection?
Boys :girls, 2:1
Does cleft lip occur on a particular side with greater frequency?
Left side more frequency
Does cleft palate have a gender predilection?
Cleft palate more common in girls
By what week in utero are the palatal shelves fused?
11th week
What % of kids with asthma are allergic to NSAIDS?
4%
How long does mast cells to degranulate and lead to bronchoconstriction?
30 minutes
What are the late phase and ultra-late phase of an asthma attack?
Late (8-12 hrs later) Airway inflammation Ultra-late phase (days to weeks later) Bronchial hyper-responsiveness
What classifies mild asthma?
Mild intermittent/mild persistent - no night symptoms - tolerates exercise - wheezing <2 days/wk
What classifies moderate asthma?
- Some night systems - Limited tolerance to exercise - Wheezing 2-5 days/wk
What classifies severe asthma?
- Frequent night symptoms - Poor tolerance to exercise - wheezing every day
What are some short-acting bronchodilators?
Albuterol B2 agonist (relaxes bronchial sm muscle), rescue inhaler Proventil, Ventolin Ipratroprium Atrovent – anticholinergic, blocks Ach receptors on sm muscle thus relaxes sm muscle
What are some long-term control meds for asthma?
corticosteroids inhaled anti-inflammatory and immunosuppressive Fluticasone (Flovent), Budesamide (Pulmicort) Prednisolone (systemic)
What is a Long acting B2 agonist (12 hrs bronchodilation)?
Salmeterol, formoterolused In combo with inhaled corticosteroids (when those aren’t controlling asthma by themselves), i.e. Advair = salmeterol + fluticasone Symbicort = formoterol + budesonide
What is LTRA – leukotriene receptor agonist?
Block leukotrienes (released by cells, responsible for asthma symptoms) Singulair (Montelukast), Accolate used for seasonal allergies and maintenance tx of asthma
What role does an anti-IgE agent Omalizuab Xolair play in controlling asthma?
Used for severe persistent asthmaRecombinant DNA IgG that binds to free IgE in blood
What drugs should you use and avoid in child with mild-moderate asthma?
N2O – appropriate AVOID narcotics, barbiturates Can use Vistaril/Atarax (hydroxyzine) antihistamine Be prepared to rescue the patient.
Management of acute asthma attack:
- Discontinue tx 2. Remove everything from mouth 3. Position pt for comfort 4. Pulse-OX 5. Inhaler B2 6. Oxygen If spO2 < 91% and struggling to breathe, Epinephrine 0.01 mg/kgcall 911
Asthma is more common in Afr Am and urban dwellers. T/F
Yes. 13.4% Afr Am, 7% urban more common in low SES Childhood prevalence is 8.5% Most common chronic medical condition of childhood.
Differential Dx of asthma includes?
- Congenital abnormality of airway - Cystic fibrosis - Immunodeficiency - GERD - Foreign body - Malignancy
Albuterol is what type of drug?
Beta2-agonist
What two classes of sedation drugs should be avoided with asthmatics?
- Barbiturates (phenobarbital) 2. Narcotics (morphine & meperidine(=demerol)) stimulate histamine release leading to bronchospasm
What drugs are recommended for sedation of child w/asthma?
- Hydroxyzine (vistaril, antihistamine) 2. Benzodiazepines (potentiate GABA’s effects, diazepam (valium), lorazepam (ativan), midazolam (versed))
T/F: Asthmatic patients tend to have increased OJ and greater incidence of posterior crossbite.
True. Also high palate and increased anterior facial height As well as…increased caries, candidiasis, erosion, decreased salivary flow, increased calculus & gingivitis
What are some cardiac defects with L to R shunts. Does this cause hypoxia?
No, but can appear as congestive heart failure over time. ASD VSD PDA AVSD Increase in pulmonary blood flow at expense of systemic circulation
What is the big R to L shunt. Does it cause hypoxemia?
Yes. Less blood to lungs, pts appear cyanotic. Tetralogy of Fallot Highest risk of endocarditis
What are some obstructive cardiac defects?
Anatomic narrowing: coarctation of aorta, aortic stenosis, pulmonic stenosis valvular, subvalvular, supravalvular Also appears as congestive <3 failure over time
What are two cases of primary pump failure?
- Dilated cardiomyopathy (limited ability of <3 to contract due to abnormality of myocardium) could be from disease, medication 2. Hypertrophic cardiomyopathy – dysrhythmias, syncope, sudden death
What is congestive heart failure?
Inability of heart to pump adequate amt of blood to systemic circulation at normal pressure to meet metabolic demands Managed medically, surgically, or combination: - remove extra fluid - improve cardiac function - improve tissue oxygenation - reduce demands on heart
What are 4 medications that help manage congestive heart failure?
- Digoxin: increase contractility of <3 2. Diuretics: decrease fluids 3. Warfarin: increases prothrombin time 4. ACE inhibitors: decrease blood pressure
At around what age is an asymptomatic ASD/VSD repaired?
Age 2-4 Repaired earlier if symptomatic. Some VSDs heal spontaneously
What is the incidence of Infective Endocarditis? (IE)
5 cases / 100,000 persons-years Less frequent in children
What are the symptoms of IE?
May appear as other infection - weakness, fatigue, rash, fever, anorexia, night sweats, arthralgia - 7–14 day typical incubation period, but may take up to 4 wks *pedo patients more likely to acquire subacute rather than acute bacterial endocarditis
What are the risks of transient bacteremia from EXT, Perio surgery, SRP, cleaning, RD placement, routine daily procedures?
EXT 10-100% Perio sx 36-88% SRP 8-80% cleaning 40% RD placement 9-32% Toothbrushing/flossing 20-68% Toothpicks 20-40% CHEWING FOOD 7-51%
What do you do if you inadvertently miss the abx px?
Give dose within 2 hrs
If pt is already on abx, what should you do?
- Delay dental procedure for 10 days to allow normal flora to re-establish 2. OR choose abx from another class (azithromycin or clindamycin)
Describe primary and secondary process of hemostasis: 1. Platelet aggregation 2. Coagulation cascade
- Primary – platelet aggregation - aggregation caused by injury - release vWF & collagen fibers from endothelium - platelets adhere - vasoconstriction occurs 2. Secondary - coagulation cascade - Extrinsic pathway activated when injury exposes blood to TF - Intrinsic pathway produces F X - Common pathway generates thrombin
What are the 3 phases of coagulation?
Initiation Amplification Propagation
Describe the 3 steps of initiation:
Initiation: 1. TF binds VII 2. TF-VII activates IX + X 3. Xa + Va to produce small amt of thrombin
Describe the 3 steps of Amplification:
Amplification – occurs mainly in platelets 1. Uses thrombin from initiation activates V, VIII, IX (5, 8, 9) 2. Releases VIII from vWF 3. Ends with Va and VIIIa being bound to activated platelets (5a, 8a)
Describe Propagation in 4 steps:
Propagation: 1. Activated VIII + IX form complex in platelet 2. This complex VIII-IX activates X 3. Xa binds with Va to form prothrombinase complex 4. Prothrombinase complex converts prothrombin to thrombin
How does fibrinolysis happen?
Plasmin dissolves fibrin clotRegulated by antiplasmin and plasminogen activator inhibitors
What does warfarin inhibit?
Production of Vit-K dependent factors (II=prothrombin, VII, IX, X) effects can be reversed by administering fresh Vit K1 Onset and duration of action of single dose is 2-5 days
How does Pradaxa act as an anticoagulant med?
Pradaxa is a competitive, direct thrombin inhibitor - prevents clot development - prevents conversion of fibrinogen to fibrin
What are 5 screening lab tests for bleeding?
- PT – EXTRINSIC – tests for defects in V, VII, X, thrombin, fibrinogen (normal is 1-18 seconds ) 2. PTT – INTRINSIC – tests for defects in V, VIII, X, XI, thrombin, fibrinogen 3. Platelet count (normal = 140,000 – 340,000) 4. Platelet function (PFA-100) – more accurate than bleeding time 5. Bleeding time – inaccurate in young children (1-6 min)
Name 2 low, 4 intermediate, and 3 high risk for bleeding dental procedures.
LOW 1. supragingival restorations or px 2. infiltration anesthesia INTERMEDIATE 1. Sub-g restoration 2. single EXT 3. RCT 4. Nerve blocks HIGH 1. Multiple EXTs 2. Perio sx 3. Gingival curettage
What is the most common inherited coagulation disorder?
Von Willebrand disease 1% of populationdeficient or defective vWF (= plasma protein in endothelium) AUTOSOMAL DOMINANT INHERITANCE low levels of VIII (may have longer PTT) vW binds to VIII to protect it in blood prolonged bleeding time abnormal platelet function test VWD is a primary process defect (defect in platelet #/function) longer bleeding time, bleeding from superficial and deep cuts, petechiae, small multiple ecchymoses, spontaneous bleeding
2 ways to manage vW disease?
DDAVP (for mild Hem A or vWD) * synthetic analog of desmopressin. POTENT ANTIDIURETIC. Decrease fluid replacement rate. - causes rapid release of VIII & vWF (doubles levels) - peak effect 1 hr after administration, 30-45 min to take effect - IV or subQ - Stimate nasal spray (can repeat q24hrs, limit fluid intake 12-18 hrs) Amicar (aminocaproic acid) (prevent clot dissolution) - antifibrinolytic – inhibits plasminogen to plasmin - 2 hrs peak effect - IV or PO (50 mg/kg q6h until healed, 7 days) - may be given alone or with DDAVP - inhibits salivary enzyme fibrinolysis
Thrombocytopenia is an insufficient # of what?
Platelets Could be due to low production (aplastic anemia, BM cancer) increased breakdown of platelets (Idiopathic thrombocytopenic purpura or drug-induced immune thrombocytopenia) Symptoms: bruising, epistaxis, gingival bleeding, petechiae CBC – low platelets PTT, PT normal another primary process defect like VWD
What are the two most common Hemophilias?
Hemophilia A – 85% - Factor VIII (think ATE/EIGHT) Hemophilia B – 15% - Factor IV (think benign) Christmas 1/3 of cases are new mutations X-linked recessive inheritance secondary process defect (defect in coagulation pathway)